This invention relates generally to implantable medical leads, and more particularly to cardiac pacing leads and methods of their delivery. As discussed in the article, "Atrial Septal Pacing: A method for Pacing Both Atria Simultaneously", by Spencer et al. published in PACE, Vol. 29, November, 1997, pp. 2739-2745, it is possible to pace both atria with a single active fixation electrode appropriately located in the anterior portion of the right side of the atrial septum separating the right and left atria. However, using present lead technologies, accurate placement of a lead at this desired site, typically located adjacent and slightly above and anterior to the ostium of the coronary sinus can be relatively difficult. While delivery of cardiac pacing leads or other electrode catheters to desired locations within the heart by means of a deflectable or pre-curved guide catheter is known, typically the location of the lead to be so delivered must be determined flouroscopically. As the lead is to be placed while the heart is beating, placement even using a guide catheter is not as simple as would be desired.